Hydrogen is an almost perfect energy source. It combines with oxygen to produce energy and water with no greenhouse gases. The problem is, hydrogen rarely occurs by itself in nature. There are basically two ways to produce usable hydrogen - through steam reforming or electrolysis.
The chemical equation for steam reforming is CH4+H2O->CO + 3 H2. Practically, it means you mix a hydrocarbon such as methane with steam to produce hydrogen and carbon monoxide. Electrolysis is greener, but costs at least three times as much as steam reforming.
In 2003, the Bush administration announced amid great fanfare the nation would collaborate with Europe to eliminate dependence upon petroleum and decrease the production of greenhouse gases. The missing piece though, was how to generate the hydrogen. The next generation nuclear reactor was envisioned to provide a more efficient electrolysis. Unfortunately, that has not panned out.
But 'Inexhaustible' Source of Hydrogen May Be Unlocked by Salt Water, Engineers Say tells that a combination of chemistry and biology may be the missing piece to the hydrogen economy. Reverse electrodialysis (RED) produces a voltage by forcing seawater and freshwater through a stack of membranes. Previously it required too many membranes to produce sufficient voltage for electrolysis and thus producing hydrogen from mixing freshwater and seawater. The Science Daily article explains that researchers at Penn State have combined exoelectrogenic bacteria to increase the voltage produced by RED and thus enable a new method of producing hydrogen.